12. Using the equation for L you determined in step 8, the wavelength of the laser you used in the experiment, and the slope of your linear equation in step 10, find the distance of the screen from the circular aperture. Pay attention of the units used in the experiment. It may be convenient to express the wavelength in mm: 13. The distance of the screen measured in the laboratory is 100cm. Calculate the percent difference between this measured value and the value you determined from our diffraction experiment in Step 12. actual and the measured values. This percent difference is given by